IBondLab

I Bond Maturity Calculator

Value of an I-bond at its 30-year maturity.

Your I-bond numbers never leave your browser — all math runs locally.
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Try: Purchase amount=1000, Purchase year=2023 → $1,000, 6.88%, $7,609, $6,609

How to use

I-bonds stop earning at 30 years. The calculator compounds the purchase-year composite for the full term.

FAQ

What happens at 30 years?

Interest stops; you can redeem at the final value or, in some cases, roll into a new bond.

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